a) Field of the Invention
The invention is directed to a rinsing tray system for cleaning the pipette tips of a multipipetting device.
b) Description of the Related Art
A feature common to all multipipetting devices is that they simultaneously take up liquids into the pipette tips from supply vessels so that these liquids can then be emptied into one or more vessels again, namely, Terasiki plates or microtitration plates, as they are called.
These multipipetting devices mostly operate on the principle of air displacement. That is, e.g., 96 pistons (arranged in an 8.times.12 grid pattern) are moved by a common driving means and generate a vacuum or overpressure in 96 air spaces formed by the piston seal and the pipette tip, so that liquids can be taken up or emptied into the microtitration plates.
The microtitration plates have depressions or wells for receiving liquids, wherein the wells are arranged in an 8.times.12 grid pattern and generally have a distance from center to center of 9 mm.
There are basically two ways of handling microtitration plates. Either the microtitration plate is brought to the pipette tips of the multipipetting device by means of a lifter or the pipette ties along with the entire pipetting arrangement are brought to the microtitration plate.
In a number of cases of application, it is desirable not to exchange the pipette tips of the multipipetting device, but rather to wash them out and clean them with a rinsing agent. Often, this is done by taking up liquid into the pipette tip from a refillable vessel and then emptying it out again into another drop vessel, as it is called. This process is usually repeated several times. The rinsing or cleaning is time-consuming principally because the appropriate vessel must be brought over and then brought back again, and the drop vessel must then be brought over and brought back again. This requires not only a minimum transporting distance corresponding to the dimensions of the vessels, but also necessitates additional space in the device.